A turbomachine combustion chamber comprises two walls forming bodies of revolution that are situated one inside the other and that are interconnected at their upstream ends by an annular chamber end wall. The chamber end wall has a plurality of openings distributed around the longitudinal axis of the chamber with a mixture of air and fuel being injected therethrough.
The chamber is surrounded by an outer annular casing having radial orifices for mounting fuel injectors in the chamber, each of these orifices being formed in an outer boss of the casing.
Each fuel injector is substantially L-shaped and has an arm extending substantially radially through one of the orifices of the casing and a head that extends substantially axially downstream from the radially-inner end of the arm. The radially-outer end of the arm, situated outside the casing, is connected to fuel feeder means.
The downstream end of the injector head is engaged in a mixer mounted in one of the above-mentioned openings in the chamber end wall. The arm of the injector has an outer collar that presents orifices for passing screws for fastening the injector on the boss of the casing.
In the prior art technique, when the injector head is engaged in the mixer, the collar of the injector arm bears against the boss of the casing. Operations of mounting and dismantling an injector comprise in particular a step that consists in moving the injector in translation (through a distance L) parallel to the axis of its head, in an upstream direction so as to disengage it from the mixer or in a downstream direction so as to engage it in the mixer. In one prior art embodiment, the injector is movable from a set-back position to an advanced position through a distance L of 9.17 millimeters (mm) in order to enable the injector to be dismantled. Nevertheless, this distance L is very penalizing since it increases the overall axial size of the engine, and thus its length, which leads to an increase in the weight of the engine, where such an increase is always harmful in aviation.
When the turbomachine includes an axial-centrifugal compressor, the diffuser that is arranged between the compressor and the chamber, inside the outer casing, can impede moving injectors in the upstream direction for dismantling purposes. In practice, it is necessary, for example, to leave clearance of 3.8 mm between the downstream end of the diffuser and the injector when the injector is in its furthest-back position (i.e. when it is situated furthest upstream), so as to enable the injector to be removed completely.